Most heavy-duty vehicles include a powertrain driven by an internal combustion (IC) engine. The air required for combustion is normally collected from outside of the engine compartment through an air intake. In order to minimize the amount of potentially damaging particulates introduced into the engine cylinders, the intake air is passed through an air cleaner that mechanically filters the air before it is discharged into the engine.
While it is feasible in some vehicles to locate the air cleaner in the vehicle's engine compartment, for heavy-duty trucks, such as a Class-8 vehicle, it is advantageous to mount the air cleaner to an external portion of the truck. Mounting the air cleaner to an external portion of the vehicle exposes the air cleaner body, which houses the filter, directly to the air stream. Because the air cleaner body is exposed to the air stream instead of the warm air in the engine compartment, the air discharged from the air cleaner to the engine has a lower temperature. As a result, the air-fuel mixture combusted in the engine has a denser charge, allowing the engine to generate more power.
Although mounting the air cleaner to an external portion of the vehicle increases the charge density of the air-fuel mixture, exposing the air cleaner to the air stream creates drag, thereby reducing the aerodynamic efficiency of the vehicle. Thus, it is desirable to provide an externally mounted air cleaner that creates less drag than currently known air cleaners.